PR: 2295

[openssl.git] / crypto / dsa / dsa_ossl.c

diff --git a/crypto/dsa/dsa_ossl.c b/crypto/dsa/dsa_ossl.c
index 4fead07e80f44398788f9a380a537ff3ae49ac2f..1fb665ec57414d3da49a2c11ff8334a9c80d89ca 100644 (file)
--- a/crypto/dsa/dsa_ossl.c
+++ b/crypto/dsa/dsa_ossl.c
@@ -185,7 +185,7 @@ static DSA_SIG *dsa_do_sign(const unsigned char *dgst, int dlen, DSA *dsa)
        if (!BN_mod_mul(&xr,dsa->priv_key,r,dsa->q,ctx)) goto err;/* s = xr */
        if (!BN_add(s, &xr, &m)) goto err;              /* s = m + xr */
        if (BN_cmp(s,dsa->q) > 0)
-               BN_sub(s,s,dsa->q);
+               if (!BN_sub(s,s,dsa->q)) goto err;
        if (!BN_mod_mul(s,s,kinv,dsa->q,ctx)) goto err;
 
        ret=DSA_SIG_new();